Variometer



Feb. 20, 1923. 1,446,155. C. R. DUMBLE.

VARIOMETER.

FILED JULY 24| 1922. 2 SHEETS-SHEET- 2- Patented Feb. 2o, 11923.

z UNITED srA'i'ias.v

PATENT OFFICE.

CLIFFORD R. DUMBLE, ARLINGTON, MASSACHUWSETTSQASSIGNOR OF ONE-HALF T0 WILLIAM G. MITCHELL,` 0F MALDEN, MASSACHUSETTS.

VARIOMETER.

Application filed July 24,

To all whom it may concern:

Be it known that I, CLIFFORD R. DUMBLE, a citizen ofthe United States of America, and resident of Arlington, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in Variometers, of which the following is a specification. i

This invention concerns radio apparatus and relates more particularly to variometers of the spherical type.

Principal objects of the present invention are to provide. a va'riometer of the above ltype which may be mounted either upon a horizontal baseboard or vertical panel as de.-

sired without necessitating a change in the' position 0f the rotor shaft; to provide means for limiting the angular extent of movement'r of the rotor to an amount sulicient to provide a maximum/variation in inductance; to .provide simple means for retaining the rotor in any desired position o1" adjustment.; to provide protecting inea-ns for the windings of the stator; andfto provide casings or frames for both stator and rotor of simple and durable design and suchas may bemanufactured with` a minimum expenditure of `time and labor. I'

Briefly stated the yi'r'iventionconsists in forming the rotor casing or frame from a pair Vof like hemispherical shells having their edges secured together, thereby formin, r a hollow spherical casing upon the eX- terior surface of which the rotor windings are mounted, and similarly foi-ming the stator casing or frame as a hollow sphere having the stator windings secured to its inner concave surface. As each half of each casing is like its complemental half, it is possible to mold all of the parts by the use of but two different molds and the shape ofv the shells is siich as to permit of their being molded in molds of simple form, thus greatly facilitating the operation and decreasing the cost thereof. The meeting edges of the hemispherical shells forming the stator frame are provided at 90o intervals with radiall grooves of semi-circular cross-section, the grooves of each shell being complemental to those ofthe other and linV the complete structure constituting bearing 1922. Serial No. 576.966.

Openings for the rotor shaft. The stator frame is thus provided with two sets of bearings for the rotor shaft, arranged at right angles to each other, permitting the statoli` frame to be rotated in the'plane of the meeting edges of the shells of which it is formed, so as to bring either set of bearing openings into engagement with the rotor shaft. Usuallythe rotor shaft extends horizontally through the vertical panel of the apparatus and is providedvwith a handle at the frame is strengthened by means of ribs' and fianges outstanding from its outer surface. To retain' the rotor-in adjusted position, a frictional device is employed, preferably consisting of a compression spring encircling the rotor shaft and bearing'at oppo` site ends against the stator and rotor frames, respectively. For limiting rotation of the rotor, the shaft is provided with a pin moving in a substantially'semi-circular groove in the stator frame, such groove being concentric with the shaft bearing and terminat.

ing in abrupt shoulders constituting abut- `ments with which the pin may contact.

In the accompanying drawings a preferred embodiment of the invention is illus- .trated by Way of example and 1n such drawm s.

igure l is a side elevation, partly in vertical cross section Ashowing the device of the present invention, the rotor shaft being verl tical. 1

. Figure 2 is an end elevation of the same device, but showing the rotor shaft as arran d horizontall i i igure 3 is an end elevation showing the rotor shaft as arranged vertically, one half of the "casing orv fra-me for the stator being removed to show the interior construction. c

' F'gnre t is a bottom plan view of the oomplete device.

` Figureis a fragmentary, vertical cross section on the line 5,-5 Figure 3, the rotor shaft being removed,

Figure-6 is a fragmentary vertical cross f section on the line 6-6 of Figure -1. p

Figure 7 is a. fragmentary, disassembled view illustrating the mode of connecting the consists of a substantially hemispherical shell, I

`parts of the rotor frame. l

Referring now to the drawings for a more detailed description of-the device, the variometer is shown a's comprising a stator frame or casing formed of two complemental and substantially like parts. Each of such parts tending circumferentially about the frame or casing. These flanges are provided with openings such as 5 for the reception of bolts or screws, 5a, by. means of which the shells l are suitably secured together. rlhe fianges,

3, 4f, are wldened at one'portion of their peripheries, as indicated at l6, 7, respective-ly, Ithus forming outstanding ears to which base flange members 8, 9, respectively are secured. 'lhese base flange members provide aligned support engaging surfaces 13, 141. which lie in a plane lsubstantially perpendicular to theI plane defined by the meeting faces of the flanges 3, 4f. 'lhe flange. members 8, 9 are provided with openings 10, 11 respectively,

for the reception of bolts or other attaching means whereby the variometer may be mounted upon a suitable support. From the central portion of such base flangesS. 9 respectively, strengthening ribs or flanges 15,

16 extend to the outer surfaces of the shells 1, 2 respectively, suc-h strengthening flanges being integrally united with 'the shells and A`respectively, outstanding from the outersiir-l with the ears 6, 7., y

Eanh'of the shells is provided with a polar opening such'as 17, the plane of which is substantially parallel to the Vplane of the meeting edges of the Hanges 3, t, these openings being definedby annular Hanges 18, 19

faces of the respective shell members. Each' of the shells is provided with a series of ribs 21, 22 respectively outstanding radially from its outer surface, such ribs lying in meridian planes and extending from the ange 3 to the flange 18, and from the dange t to the Flange 19, such ribs serving greatly to strengthen the shells which may/thus be made of 'relatively thin material. 'llhese ribs are prefnatale@ erably of tapering4 cross section to facilitate `the drawing of the completed shell from the mold. .'lhe inner surface of each hemispherical shell member is substantially smooth and of spherical curvature, and against such surface of each shell is secureda winding 23, of insulated wire which may be secured directly to the shell by means of anysuitab-le cement. rlhe windings 23 of the two shell me-mbersare connected in series at their ad* jacent ends while the other' terminals of such windings are secured to binding posts 24:,'25 respectively. l

Within the stator casing thus provided, a

rotor casing or frame is arranged. This rotor casing or frame is also preferably formed of two substantially like and complemented hemispherical shells 26, 27 togetherA constitilting a substantially spherical hollow sup` port for the windings of the rotor. rlhese parts, 26, 2 7, Aare provided respectively withl angemembers 28, 29 (Fig. 7) at their meeting edges together constituting an equitorial rib surrounding the rotor casing. At diametricallyv opposite points in such flange members, ears such as 30, 31 project therefrom, one ear of each flange being at a somewhat greater radial distance from the center of the shell than-the other `so that when assembled one ear of each vflange may overlap the corresponding ear of the other (see Fig. 6). 'llhese ears are provided with openings such as 32, 33 through which pass stubshafts 34, 35. Theseshafts. when the parts are as sembled, are aligned with one another and define the axis about which .the rotor turns. Preferably, these shafts are screw threaded at their inner ends for the reception of nutsv 36 by means of which they are @cured in place, at the same time holding the members 26,27 of the rotor frame in operative engagement. Each of the rotor shell members 26, 27 is provided with an opening, the plane of which is substantially parallel to that of thev meeting edges of the 'flanges 28, 29. such openings being defined by outstanding flanges such as 37.

A rotor windingis secured tothe outer surface of each of the'members 26, 27, respectively, extending between the central idanges 23, 29 and the respective lianges37, .these windings being secured by cement. 'llhe windings ofthe two halves of the rotor shell are arranged in series, adjacent ends thereof being connected while the other terminal of one such winding is grounded on one of the shafts, as for exam le, shaft 3d. rlhis shaft is preferably ho low and the terminal t0 of the other' winding passes out through the opening in such shaft. A lsuitable lead Wire 39 may be secured to the shaft 34 outsidev its ,bearing in the stator frame. v

The stator frame is preferably provided 1,44a,1cs

with two` pairs of aligned journal-opening, one pair of such openings being shown at 41, 42 respectively, Figure 3whi1e in such figure the shafts 34,35 occupy the other pair of aligned openings, one of the latter openings being shown at 43 in Fig. 5.' These openings are preferablyformed by providing grooves of semicircular-cross section in the meeting flanges 3, 4 of the stator frame, four such grooves being provided for each frame, spaced 90.o apart from veach other. When the flanges 34 are secured together, these semicircular grooves form journal openings of proper form for the reception of the rotor shaft elements.

Associated with the journal opening43- of one pair is a recess 44 of a diameter some'-A what greater than that of the journal opening and concentric therewith, such recess being of substantiallyA semicircular extent and serving for the reception of a pin 45 projectingfrom one of the shaft members as, for example, the shaft 35. Thispin moves freely in the recess 44 but is limited in its movement by engagement alternatively with theshoulders 46, 47 which terminate such recess.- A similar recess cooperating with the journal openings 42 is shown at 48.

A coiled .compression spring 49 lsurrounds the shaft 34, one end of such spring bearing against the inner surface of the stator frame or casing whilethe other end of such spring engages the outer surface ofthe rotor frame. This springis normally 'compressed and thus serves'as a-frlction brake to oppose turning of therotor frame.

The variometer thus constructed is of extremely simple form. The stator frame and 'the rotor framer eachl consists merely of two like parts suitably secured together so that it is only necessany for the manufacturer to provide two molds for usey in 45 making up a variometer of this type, one

of such molds serving. or forming -tlhe halves of the stator frame while the other is employed in making the halves of the rotor frame. The form of the parts, furthermore, is such as to permit the employment of molds Aoffvery simple character so that the cost of construction of the frame .y members is reduced to a minimum. Moreover, the design is suoli as to secure a maximum of stren h with a minimum quantity of material, w ile at the same time providing a continuous supporting shell for the stator windings which serves to protect the latter from accidental injury.

By the provision of two pairs of journal openings in the vstator frame, it is possible, while maintaining the rotor shaft in a given v position, to rotate the stator frame through an angle of 90, thus permitting such stator frame to be" mounted upon'either a hori- .manlpulation lof latches or'other. ho

The spring 49 which constitutesl a friction brake contributes t`o the proper maintenance v of the rotor in adjusted position, such spring tending to retain the parts in-any position of adjustment ,but without necessitating the din devices and without interfering with an? desired and intentioned adjustment of the rotor.

While aspecifc arrangement has herein been described, it is to be understood that various changes and rearrangements of parts as well asmodifications of the shape thereof may well be made without departing from the spirit of the invention.

What I clalm and desire to secure by Letters Patent of the United `States is:

.1. A variometer Vhaving a stator frame comprising a pair of`like,

hemispherical shells,

each shell having an equatorial flange,

an ear extending outwardly from the edge of each flange, a base member projectingv from each ear, and means for Securing said flanges' together with the base members lying ln-the same plane. I

2. A variometer having a' stator frame comprising a hemispherical shell having a radial, equatorial flange and a polar opening. Aa flange surrounding the latter opening, and

a-plurality of ribs outstanding from the outer surface of said shell and terminating in the respective flanges. A

3. A variometer having a stator frame comprising a hemispherical shell of'k relatively thin material having a radial equa.- torial flange and a polar opening, a' flange surrounding said opening, and a plurality of spaced ribs, defining meridian' planes, connecting said flanges and projecting from the outer face of the shell.

4. A variometer having a stator frame comprising a hemispherical shell of relative spaced ribs .projecting integrally from the outer surface of saidshell and defining me- -ridian planes.

.5. A variometer having a stator frame comprising a hemispherical shell of 'relatively thin material, and a plurality of ribs, tapering outwardly i-n cross section, projecting from the outer surface of the shell and" serving to strengthen the same.l

6. A variometer comprising a hemispheri- 130 y thin material, and a plurality of 120 cal shell havingl a radially projecting ear lying in its equatorial planesv and. a base- -trom substantially in the plane of its equatorial edge, a base flange united With said near and having a support engaging surfacee and a brace member extending from the base flange to the outer peripheral surface ot the shell.

9. A. variometer comprising a pair oi coinplemental hollow shells arranged With their cavities opposed to each other, an ear prol ljecting from each of said shells, a flange carried byv each ear, said flanges having support engaging surfaces lying lsufbstantially in the same plane., and brace members uniting the ears with their respective flanges.

l0. A variom'eter comprising a spherical stator trame, and means for supporting saidA frame, saidv frame having radial journal openings disposed in an equatorial plane and arranged at an angle to one another.

1l. A variometercomprising a spherical stator frame, anda rotor having-oppositely extending shaft elements, said trame having a pair of aligned journal openings for the respective shaft elements', and a second pair of aligned journal openings disposed at, an'

angle to said irst pair.

12. A varlometer comprising a hollovv spherical stator trame having a base mem-` ber, a spherical rotor trame arranged With-.-

inthe stator trame,'said rotor frame having a shaft, and bearings 'in the stator frame ariyeea) lee ranged at right angles to each other and alout varying the position of the rotor shaft.

13. A variometer comprising a stator lframe having a base member provided with a support engaging surface, a rotor having .opposltelyfextending shaft elements, said stator trame having -a pair ot aligned journal openings for the respective shaft ele- -ments, the axes of said openings lyingv in a plane' perpendicular to that of said support engaging surface, and a Second pair oi' 'aligned jou'rnaled openings having their axes disposed at right angles to the axesot said first openings.

la. A variometer comprising al stator '-frame, and a base therefor provided With a support engaging surface7 said trame hav i ing a pair or aligned journal openings Whose axes lie in plane perpendicular to said supporting surface, and a second pair or aligned journal openings Adisposed at right angles to the openings of said iirst pairvand in the ings of one pair being perpendicular to said 4supporting surface.

tey

plane thereof, the axes of the journal openprovided with a support engaging surface, l

a rotor Within said frame having oppositely extending shaft elements, aligned diametrally opposed radial journal openings in said stator trame, said openings being disposed in a plane perpendicular to said support engaging surface,` and having their axes perpendicular'to said surface, and a Second pair ot diametrally' opposed journal openings yin said frame' lying in the same plane as the 'irst openings but with their axes parallel to' said surface. 4

Signed by me at Boston',` Massachusetts, this 12th day Yoi? July,1922.

cnirronn n. entrera. 

